public class Main {
    public static void main(String[] args) {
        System.out.println("Hello world!");
        MySingleList mySingleList=new MySingleList();
        mySingleList.createList();
        mySingleList.display();
        System.out.println();
        System.out.println(mySingleList.size());
        System.out.println(mySingleList.contains(12));

    }
}